Pre-trade risk checks are rules that an exchange or broker applies to every order before it reaches the market. They confirm that the account is allowed to trade, that it has enough funds or margin, and that the order stays within size, price, and position limits. An order that fails a check is rejected before it can execute, which is meant to stop erroneous orders and trades the account could not pay for.
Last updated: November 2, 2026.
What do pre-trade checks look at?
Each check answers one question about the order or the account behind it.
| Check | What it prevents |
|---|---|
| Account permissions | Trading a market the account is not approved for |
| Balance or margin | A trade the account cannot pay for or support |
| Order size limit | An order far larger than intended, such as a typing error |
| Price band | An order priced far away from the current market |
| Position limit | A position that grows past the maximum set for the account |
| Order rate limit | A flood of orders that could overload the venue |
Account permissions can reflect identity checks, the account's region, or the products a customer has been approved for.
Why check before the trade instead of after?
Once a trade executes, the other side expects to be paid. If the buyer cannot pay, the trade fails to settle, and someone has to absorb the gap or unwind it.
In traditional markets, regulators in several jurisdictions require brokers that give clients access to an exchange to apply pre-trade controls. Exchanges also apply their own checks, such as price bands that reject orders too far from a reference price.
How do pre-trade checks work onchain?
On an onchain venue, the checks can live in the same smart contract or chain logic that accepts orders. Balances are already onchain, so the venue can confirm funds directly instead of trusting a separate record. An order that fails a check is rejected in the same transaction, and nothing executes.
Onchain settlement can also be atomic: the trade and the transfer of assets happen together, or neither happens. That removes the case where a trade executes but the funds never arrive. The guide to cross-chain settlement explains what changes when the two assets sit on different networks.
Who sets the limits?
Usually several parties. The venue sets baseline rules for every market. A broker or operator adds limits for each client. Trading firms often add their own limits inside their systems, so an order can pass through more than one layer of checks before it reaches the matching engine.
FAQ
What is the difference between pre-trade and post-trade risk?
Pre-trade checks decide whether an order is accepted. Post-trade risk management watches positions after trades execute, for example by calling for more margin or liquidating a position whose collateral has fallen too far.
What happens when an order fails a check?
The order is rejected, usually with a reason code, and nothing is traded. The account can correct the order and send it again.
Do pre-trade checks slow trading down?
They add a step to every order. Venues build that step into order entry, so it runs before the order reaches the matching engine. The guide to crypto exchange backends shows where the risk engine sits.
Build trading across chains
For tools to build applications that work across chains, see LayerZero developer resources.